1. Technical Field
The present invention relates to a return lever member, a feed device including the return lever member and a feed roller, a recording apparatus including the feed device, and a liquid ejecting apparatus including the feed device. The feed roller picks up a recording medium from a recording media stacked on a stacking unit and feeds the recording medium downstream via a feed path. The return lever member pushes back upstream another recording medium that has unnecessarily entered the feed path in feeding a necessary recording medium downstream.
A liquid ejecting apparatus used herein is not limited to an ink jet recording apparatus, copier, and facsimile machine, which record information by ejecting ink onto a recording material (e.g., recording paper) from a recording head as a liquid ejecting head. Other examples of the liquid ejecting apparatus include an apparatus that attaches liquid for a specific application, instead of ink, to an ejecting target medium corresponding to the recording material by ejecting the liquid to the ejecting target medium from a liquid ejecting head corresponding to the recording head. Examples of the liquid ejecting head include, in addition to the above-described recording head, a color-material ejecting head used in production of a color filter for a liquid crystal display or other apparatuses, an electrode-material (conductive paste) ejecting head used in formation of an electrode for an organic electroluminescent (EL) display, a surface emitting display (FED), or other apparatuses, a bioorganic-substance ejecting head used in production of a biochip, and a sample ejecting head as a precision pipette.
2. Related Art
A feed device in a known recording apparatus includes a hopper on which sheets of paper are stacked, a feed roller that picks up the uppermost sheet from the sheets of paper, and a return lever member that pushes a sheet of paper that has unnecessarily entered a feed path by its own weight or other reasons back to the hopper, as disclosed in, for example, JP-A-2000-289873. The return lever member can pivot to two positions, one being a protruded position and the other being a retracted position with respect to the feed path. One example of such a known feed device is illustrated in FIGS. 18A and 18B.
As illustrated in FIG. 18A, a feed device 500 includes a hopper 501, a feed roller 502, and a return lever member 503. The return lever member 503 includes lever units 507 which pushes a sheet 506 back by coming into contact therewith and a lever rotating shaft 505a being a base and formed integrally with the lever units 507. The lever units 507 are disposed between the feed roller 502 and a pair of transport rollers (not shown) in a feed direction. The lever units 507 are substantially equally spaced from the least significant digit (LSD) side (i.e., the right side in FIGS. 18A and 18B) to the most significant digit (MSD) side (i.e., the left side in FIGS. 18A and 18B) so as to cover the entire range of a feed path 504 for guiding the sheet 506 to the pair of transport rollers (not shown) in a main scanning direction X, which is the direction of width of the sheet 506. In other words, the lever units 507 are aligned over the full range in the main scanning direction so that the lever units 507 can push back the sheet 506 that has unnecessarily entered the feed path 504 even if the sheet 506 has a long size in the main scanning direction X.
However, since the lever units 507 are integral with the lever rotating shaft 505a, which has a long size in the common main scanning direction X, the return lever member 503 is an elongate component in the main scanning direction X as a whole. This may cause difficulty in dimensional control. In addition, the long length of the return lever member 503 in the main scanning direction X may significantly increase costs and may create distortion thereof caused by twisting. One approach to addressing these problems is to remove one or more lever units 507 in the MSD side to have a short lever rotating shaft 505b, as illustrated in FIG. 18B.
In this case, however, it is difficult to provide the lever units 507 to the full range in the main scanning direction X in the feed path 504. If the sheet 506 is relatively long in the main scanning direction X, the places of the lever units 507 may be biased toward the LSD side with respect to the center in the direction of width of the sheet 506 (X). In this case, unfortunately, frictional resistance generated between the feed path 504 and the sheet 506 when the return lever member 503 pushes back the sheet 506 may cause an MSD-side end of the sheet 506, which is not in contact with the lever units 507, to be located downstream of an LSD-side end of the sheet 506, which is in contact with the lever units 507.
The weight of the sheet 506 may also causes the MSD-side end of the sheet 506, which is not in contact with the lever units 507, to be lower than (downstream of) the LSD-side end of the sheet 506, which is in contact with the lever units 507.
That is, there is the possibility of being unable to reliably push back the sheet 506 unnecessarily entering the feed path 504. The same applies to a case in which the number of the lever units 507 is small.